This invention is related to a medical boot for orthotic or wound care applications having an outer fabric cover formed of a continuous layer of fabric loops that are engageable with fabric hook material, and a trilaminate detachable sole having an upper surface with fabric hooks that are releasably engageable with the fabric loops of the boot sole.
In my prior patents and applications I have disclosed a variety of applications for a soft, flexible fabric boot body that protects a user's heel from decubitus ulcers for patients with heel, toe and foot pressure. I have also disclosed a splint and a hard inner sole that can be mounted in the boot to support the user's foot when he is lying on his back. See for example my U.S. Pat. No. 5,367,789 which was issued Nov. 29, 1994, for "Protective Medical Boot and Orthotic Splint".
In some cases the user may desire to walk while wearing the boot, either with a hard splint, a hard inner sole, or with no stiff structure between the bottom of his foot and the boot sole. For this reason I disclosed a resilient detachable exterior sole in my co-pending application Ser. No. 08/343,090, filed Nov. 21, 1994, for "Protective Medical Boot and Orthotic Splint".
Another form of a resilient detachable exterior sole that could be releasably attached to the medical boot was illustrated in my U.S. patent application Ser. No. 08/521,962 for "Medical Boot with Unitary Splint". The exterior sole has a cushioned mid-section, a bottom laminate with a formed ground-engaging bottom surface, and an upper laminate of a continuous layer of hook-shaped fabric type fastener material which can be readily attached to the bottom cover of the boot. The exterior detachable sole can be readily attached to the boot when the user wants to walk, or be removed from the boot when the patient is lying down.
Some prior art such as U.S. Pat. Nos. 5,569,173 and 5,569,174, which issued to Harold T. Varn on Oct. 29, 1996, for "Foot Orthosis with Detachable Sole Plate" use fabric hook fastener strips that are parallel to the length of the patient's foot. One problem with such strips is that the ground-engaging layer of the detachable sole is relatively thick and stiff. If the strips of fasteners are not sufficiently wide and aligned, the sole separates from the boot as the patient walks. The hole in the sole (Varn) for access to a nut and bolt assembly must register with the hole in the bottom layer of the boot, or misalignment may cause the sole to separate from the boot.
Varn's splint utilizes a nut and bolt to extend a toe piece to create a larger size. This assembly creates a posting area in the mid-section of the foot. Hook and loop strips must be attached on either side of this assembly. The loop strips are sewn to the bottom of the boot to a canvas type fabric, because a laminate type of fabric used in my boot would be too thick and would require a much longer bolt. This would cause unwanted pressure to the plantar surface of the foot.
Also, if the nut loosens while the patient is ambulating, the toe piece could shift to the side, and thereby disengage or misalign the sole from the boot. This is especially true for all telescoping splints.